PIC16F84产生两组PWM输出的实例源程序
;**********************************************************************
list p=16F84 ; list direcTIve to define processor
＃i nclude
__CONFIG _CP_OFF & _WDT_OFF & _PWRTE_OFF & _RC_OSC
; '__CONFIG' direcTIve is used to embed configuraTIon data within .asm file.
; The lables following the directive are located in the respective .inc file.
; See respective data sheet for additional information on configuration word.
;********************** CONST DEFINITIONS******************************
FULL_WORK = 10 ; 程???㏄戳箇砞?
DEF_WORK1 = 2 ; PWM1??㏄戳箇砞?
DEF_WORK2 = 8 ; PWM2??㏄戳箇砞?
PORT_OUT = PORTB ; PWM块?梆
PIN_PWM1 = 0 ; PWM1块?竲?
PIN_PWM2 = 1 ; PWM2块?竲?
;********************** VARIABLE DEFINITIONS***************************
CBLOCK 0x0C
w_temp ; variable used for context saving
status_temp ; variable used for context saving
PWM_FULL ; 程???㏄戳璸计竟(?计)
PWM_WORK_CFG1 ; PWM1 ??㏄戳砞﹚既?竟
PWM_WORK_CFG2 ; PWM2 ??㏄戳砞﹚既?竟
PWM_WORK_CNT1 ; PWM1 ??㏄戳璸计竟(?计)
PWM_WORK_CNT2 ; PWM2 ??㏄戳璸计竟(?计)
ENDC
;**********************************************************************
;****************** 垂??竚?祘Α秈?翴 ***********************
;**********************************************************************
ORG 0x000 ; processor reset vector
ResetStart
goto main ; go to beginning of program
;**********************************************************************
;****************** い耞狝叭祘Α秈?翴 *************************
;**********************************************************************
ORG 0x004 ; interrupt vector location
movwf w_temp ; save off current W register contents
movf STATUS,w ; move status register into W register
movwf status_temp ; save off contents of STATUS register
bsf STATUS,RP0
bcf INTCON,T0IF ; 睲埃璸?竟い耞篨腹
bcf STATUS,RP0
decfsz PWM_FULL,F ; 浪琩琌?ЧΘ??㏄戳
goto ISR_PWM1
bsf PORT_OUT,PIN_PWM1 ; PWM1/PWM2?確High筿?
bsf PORT_OUT,PIN_PWM2
movlw FULL_WORK ; ?穝砞﹚???㏄戳璸计竟
movwf PWM_FULL
movf PWM_WORK_CFG1,W
movwf PWM_WORK_CNT1
movf PWM_WORK_CFG2,W
movwf PWM_WORK_CNT2
goto ISR_EXIT
ISR_PWM1
decfsz PWM_WORK_CNT1,F ; 浪琩PWM1??㏄戳
goto ISR_PWM2
bcf PORT_OUT,PIN_PWM1 ; ??㏄戳挡??盢块?砞?Low筿?
ISR_PWM2
decfsz PWM_WORK_CNT2,F ; 浪琩PWM2??㏄戳
goto ISR_EXIT
bcf PORT_OUT,PIN_PWM2 ; ??㏄戳挡??盢块?砞?Low筿?
ISR_EXIT
movf status_temp,w ; retrieve copy of STATUS register
movwf STATUS ; restore pre-isr STATUS register contents
swapf w_temp,f
swapf w_temp,w ; restore pre-isr W register contents
retfie ; return from interrupt
;**********************************************************************
;****************** ?﹍てPWM *******************************
;**********************************************************************
InitPWM
bsf STATUS,RP0 ; 砞﹚PWM1/PWM2竲?块?
bcf PORT_OUT,PIN_PWM1
bcf PORT_OUT,PIN_PWM2
bcf STATUS,RP0
bsf PORT_OUT,PIN_PWM1 ; 箇砞PWM1/PWM2块?蔼筿?
bsf PORT_OUT,PIN_PWM2
movlw FULL_WORK ; 砞﹚?既?竟ぇ箇砞?
movwf PWM_FULL
movlw DEF_WORK1
movwf PWM_WORK_CFG1
movwf PWM_WORK_CNT1
movlw DEF_WORK2
movwf PWM_WORK_CFG2
movwf PWM_WORK_CNT2
retlw 0
;**********************************************************************
;****************** ?﹍て璸?竟 *******************************
;**********************************************************************
InitTimer
bsf STATUS,RP0
bsf OPTION_REG,T0CS ; 氨ゎ?历竟?猧块?
bsf OPTION_REG,PSA ; 砞﹚ぃㄏノ?猧箇埃竟
bsf INTCON,GIE ; ゴ秨?办い耞秨闽(い耞羆秨闽)
bcf INTCON,T0IF ; 睲埃璸?竟い耞篨腹
bcf STATUS,RP0
retlw 0
;**********************************************************************
;****************** 币笆璸?竟 *******************************
;**********************************************************************
StartTimer
bsf STATUS,RP0
bcf OPTION_REG,T0CS ; 砞﹚?历竟?猧块?(1/4 osc)
bsf INTCON,T0IE ; ゴ秨璸?竟い耞
bcf STATUS,RP0
retlw 0
;**********************************************************************
;****************** 氨ゎ璸?竟 *******************************
;**********************************************************************
StopTimer
bsf STATUS,RP0
bsf OPTION_REG,T0CS ; 氨ゎ?历竟?猧块?
bcf INTCON,T0IE ; 闽?璸?竟い耞
bcf STATUS,RP0
retlw 0
;**********************************************************************
;****************** ?祘Α秈?翴 *******************************
;**********************************************************************
main
bcf STATUS,RP0 ; select Page 0 for Port Access
call InitPWM
call InitTimer
call StartTimer
goto $
;**********************************************************************
END ; directive 'end of program'
